Electrode sealing and power connection apparatus



Jan. 27, 1959 E. D. DILLING I 2, 7

ELECTRODE SEALING AND POWER CONNECTION APPARATUS Filed Feb. 14, 1957 O INVENTOR.

' ELMER D. DILLING BY flag;

AGENT ELECTRODE SEALING AND POWER CONNECTION APPARATUS Elmer D. Dilling, Las Vegas, Nev., assignor to Titanium Metals Corporation of America, New York, N. Y., a corporation of Delaware Application February 14, 1957, Serial No. 640,190

2 Claims. (Cl. 204-246) This invention relates generally to apparatus employed for the production of metals by electrolysis and more particularly to a device for sealing and transmitting power to electrodes employed in electrolytic cells.

The electrolytic production of certain metals, for example titanium and zirconium, requires that the cells employed be sealed or isolated from the atmosphere. This is necessary to prevent contamination of product metal by atmospheric gases. In the cells employed, raw material is introduced into an electrolyte in a cell, and metal is deposited on a cathode which is periodically removed and the product metal stripped therefrom. Removing and replacing cathodes involves unsealing and rescaling the cell around the cell opening and also breaking and remaking the power connection to such cathode. Apparatus previously employed has involved laborious and time-consuming disconnection of electric leads and various relatively ineflicient methods for sealing the electrode to the cell top or cover.

It is the principal object of this invention to provide improved apparatus for sealing an electrode in an electrolytic cell and to provide a power connection thereto. A further object of this invention is to provide sealing means for an electrode employed in an electrolytic cell which when sealed and unsealed automatically connects and disconnects the power supply to such electrode. These and other objects of this invention will be apparent from the following description thereof and from the annexed drawings in which:

Fig. 1 shows a general sectional side view of an electrolytic cell embodying features of this invention.

Fig. 2 shows a top view of the cell of Fig. 1.

Fig. 3 is an enlarged sectional illustration of the sealing and power connection apparatus.

Referring now to Figs 1 and 2, an electrolytic cell in which the apparatus of this invention may advantageously be employed, comprises a container 10 which may be constructed of material designed to contain therein the electrolyte 11. For purposes of illustration the cell will -be described in connection with the manufacture of metallic titanium. It is provided at the bottom with graphite heating elements 12. An anode 13 is suspended from the top of the cell and partially immersed in the molten salt electrolyte 11. Suitable fixed sealing means at 14 are provided to seal and insulate the anode where it passes through the top of the cell. In the anode compartment may be provided a vent tube 15 for removal of gaseous products from this section of the cell. The anode is separated from the cathode by a barrier 16 extending beneath the surface of the electrolyte. A cathode 17 is partially immersed in the electrolyte on the other side of the barrier 16. Suitable feed material introduction means such as feed pipe 18 are provided, for example, to feed vaporous titanium tetrachloride into the electrolyte in the vicinity of the cathode".

As more clearly shown in Fig. 3, the cathode 17 is provided at its top with cover member 19, around the United States Patent 'ice edge of which is depending flange 20. Means forlifting and handling the cathode such as'ring 21 may, if desired, be provided on top of cover 19. Attached to the top of the cell and surrounding the openingv therein, and arranged to mate with depending flange 20, is open top channel member 22, which contains a low melting point metal 23. The low melting point metal contained in channel 22 is preferably a lead or bismuth base alloy. For example, one containing 52% bismuth, 42% lead and 8% cadmium, which has a melting point of 9l.S C., will be found to be satisfactory. The precise composition of the alloy may be selected on the basis of particular operating conditions and design and alloys containing bismuth and antimony are particularly desirable since these do not contract appreciably on cooling. Advantageously, the melting point of the alloy should be between about 70 C and 250 C. Means associated with channel member 22 are provided for solidifying and melting the metal contained therein which in the embodiment illustrated, comprise pipe 26, which is attached to the bottom of channel 22 in good thermal contact therewith. Conventional and suitable sources of cooling fluid, such as water, and heating medium, such as steam, may be circulated through pipe 26 to solidify or melt the metal 23 in channel 22 under conditions hereinafter described in detail.

Where the cathode is in operating position in the shell 10, the bottom of the flange 20 is immersed in the solidified metal 23 contained in channel 22. During the opfor proper electrical operation. When it becomes neces-.

sary or desirable to remove a cathode from the cell, a heating medium such as steam is circulated through pipe 26 to melt the low melting point metal 23. With the metal 23 molten, the seal is readily broken by simply lifting up the cathode together with its cover assembly by means of ring 21. flows from channel 22 through the metal 23, to flange 20 and to cover 19 and thus to the electrode 17, and also through incidental contact of the cover 19 or flange 20 with the channel member 22. Breaking of the seal by lifting the electrode cover flange-20 out of sealing and mating engaged with channel member 22 also automatically breaks the power connection as will be apparent. When the cathode is to be replaced or a new one substituted, it is simply lowered in place while the metal 23 is maintained molten and subsequently cooling Water circulated through pipe 26 to solidify the metal 23 thus maintaining the seal and electrical connection.

The apparatus of this invention avoids devices which involve disconnection of power leads when the cathode is to be removed and replaced in an electrolytic cell and also avoids employment of cumbersome and inefiicient methods of sealing the electrode cover to the cell top.

I claim:

1. Electrode sealing and power connection apparatus comprising an open top channel member attached to the top of an electrolytic cell and surrounding an electrode opening therein, a depending flange attached to an electrode cover and adapted to mate with said open top channel member, a low melting point metal contained in said channel member, cooling and heating means associated with said channel member adapted to solidify and melt the low melting metal contained therein, and an During operation, electric current.

electrical power connection attached to said channel nel member, cooling and heating means associated with member. said channel member adapted to solidify and melt the 2. Electrode sealing and power connection apparatus low melting metal contained therein, and an electrical comprising an open top channel member attached to the power connection attached to said channel member.

top of an'electrolytic cell and surrounding an electrode 5 opening therein, a depending flange attached to an elec- References Cited in the fil f this patent trode cover and adapted to mate with said open top channel member, a metallic alloy having a melting point be- UNITED STATES PATENTS tween about 70 C. and 250 C. contained in said chan- 2,502,888 Ravenscroft Apr. 4, 1950 

1. ELECTRODE SEALING AND POWER CONNECTION APPARATUS COMPRISING AN OPEN TOP CHANNEL MEMBER ATTACHED TO THE TOP OF AN ELECTROLYTIC CELL AND SURROUNDING AN ELECTRODE OPENING THEREIN, A DEPENDING FLANGE ATTACHED TO AN ELECTRODE COVER AND ADAPTED TO MATE WITH SAID OPEN TOP CHANNEL MEMBER, A LOW MELTING POINT METAL CONTAINED IN SAID CHANNEL MEMBER, COOLING AND HEATING MEANS ASSOCIATED WITH SAID CHANNEL MEMBER ADAPTED TO SOLIDIFY AND MELT THE LOW MELTING METAL CONTAINED THEREIN, AND AN ELECTRICAL POWER CONNECTION ATTACHED TO SAID CHANNEL MEMBER. 